Electric boat

The use of electricity alone to power boats stagnated apart from their outboard use as trolling motors until the Duffy Electric Boat Company of California started mass-producing small electric craft in 1968. It was not until 1982 that the Electric Boat Association was formed and solar powered boats started to emerge.^[15] To reduce friction and increase range, some boats use hydrofoils.^[16] The eWolf tugboat that launched in March 2024 has a 6.2 megawatt-hour main propulsion battery and two electric drives and is more powerful than the diesel tugboats at the port.^[17]

Components

The main components of the drive system of any electrically powered boat are similar in all cases, and similar to the options available for any electric vehicle.

Charger

Electric energy has to be obtained for the battery bank from some source like the sun.

• A
  green electricity it is possible to operate electric boats using sustainable or renewable energy
  . For large vessels, an onshore battery may be necessary to provide more short-term power than the grid can supply.

• Solar panels
  can be built into the boat in reasonable areas in the deck, cabin roof or as awnings. Some solar panels, or photovoltaic arrays, can be flexible enough to fit to slightly curved surfaces and can be ordered in unusual shapes and sizes. Nonetheless, the heavier, rigid mono-crystalline types are more efficient in terms of energy output per square meter. The efficiency of solar panels rapidly decreases when they are not pointed directly at the sun, so some way of tilting the arrays while under way is very advantageous.
• Towed generators are common on long-distance cruising yachts and can generate a lot of power when travelling under sail. If an electric boat has sails as well, and will be used in deep water (deeper than about 15 m or 50 ft), then a towed generator can help build up battery charge while sailing (there is no point in trailing such a generator while under electric propulsion as the extra drag from the generator would waste more electricity than it generates). Some electric power systems use the free-wheeling drive propeller to generate charge through the drive motor when sailing, but this system, including the design of the propeller and any gearing, cannot be optimised for both functions. It may be better locked off or feathered while the towed generator's more efficient turbine gathers energy.
• Wind turbines are common on cruising yachts and can be very well suited to electric boats. There are safety considerations regarding the spinning blades, especially in a strong wind. It is important that the boat is big enough that the turbine can be mounted out of the way of all passengers and crew under all circumstances, including when alongside a dock, a bank or a pier. It is also important that the boat is big enough and stable enough that the top hamper created by the turbine on its pole or mast does not compromise its stability in a strong wind or gale. Large enough wind generators could produce a completely wind-powered electric boat. No such boats are yet known although a few mechanical wind turbine powered boats exist.
• In hybrid electric boats, if a boat has an internal combustion engine anyway, then its
  series hybrid
  ).

In all cases, a charge regulator is needed. This ensures that the batteries are charged at their maximum safe rate when power is available, without overheating or internal damage, and that they are not overcharged when nearing full charge.

An alternative to charging is changing batteries while in port. It offers the benefit of removing the need to wait for the recharging to complete before sailing. This approach has the potential to allow ships and ferries with tight schedules to be electrified as charging can be done in port with no time limitations.^[18]

Battery bank

There have been significant technical advances in battery technology in recent years, and more are to be expected in the future.

• Lead–acid batteries
  were still the most viable option until the advent of larger, lithium-ion batteries mass-produced for electric cars from approximately 2012 onwards. Deep-cycle, 'traction' batteries are the obvious choice. They are heavy and bulky, but not much more so than the diesel engine, tanks and fittings that they may replace. They need to be securely mounted, low down and centrally situated in the boat. It is essential that they cannot move around under any circumstances. Care must be taken that there is no risk of the strong acid being spilled in the event of a capsize as this could be very dangerous. Venting of explosive hydrogen and oxygen gases is also necessary. Typical lead-acid batteries must be kept topped-up with distilled water.
• AGM
  batteries, minimize the risk of spillage, and gases are only vented when the batteries are overcharged. These batteries require minimal maintenance, as they cannot and usually do not need to be refilled with water.
• Nickel metal hydride, lithium-ion
  and other battery types are becoming available, but are still expensive. These are the kind of batteries currently common in rechargeable hand tools like drills and screwdrivers, but they are relatively new to this environment. They require different charge controllers to those that suit lead-acid types.
• lithium iron phosphate batteries
  , which although are heavier than other lithium-ion, is safer for marine application. They are expensive but in applications which need reliability and ruggedness like ferries which run most of the day (10–12 hours/day) this is the best option. It has a much longer life – 5 to 7 years life-cycle.
• Fuel cells or flow batteries may provide significant advantages in years to come. Today (2017) however they are still expensive and require specialist equipment and knowledge.

Among the various battery chemistry the choice between a fast charging (LTO, NMC etc.) versus slow charging (LFP) is decided by economic analysis considering Capital expenditure (CAPEX), Operating expense (OPEX), Total cost of Ownership (TCO). It is observed that for higher energy need because of high speed or large weight with intermitted charging is an area where fast charging batteries become more economical.^[4]

The size of the battery bank determines the range of the boat under electric power. The speed at which the boat is motored also affects range – a lower speed can make a big difference to the energy required to move a hull. Other factors that affect range include sea-state, currents, windage and any charge that can be reclaimed while under way, for example by solar panels in full sun. A wind turbine in a good wind will help, and motor-sailing in any wind could do so even more.

Speed controller

To make the boat usable and manoeuvrable, a simple-to-operate forward/stop/backwards speed controller is needed. This must be efficient—i.e. it must not get hot and waste energy at any speed—and it must be able to stand the full current that could conceivably flow under any full-load condition. One of the most common types of speed controllers uses pulse-width modulation (PWM). PWM controllers send high frequency pulses of power to the motor(s). As more power is needed the pulses become longer in duration.

Electric motor

A wide variety of electric motor technologies are in use. Traditional field-wound DC motors were and still are used. Today many boats use lightweight permanent magnet DC motors. The advantage of both types is that while the speed can be controlled electronically, this is not a requirement. Some boats use AC motors or permanent magnet brushless motors. The advantages of these are the lack of commutators which can wear out or fail and the often lower currents allowing thinner cables; the disadvantages are the total reliance on the required electronic controllers and the usually high voltages which require a high standard of insulation.

Drive train

Traditional boats use an inboard motor powering a propeller through a propeller shaft complete with bearings and seals. Often a gear reduction is incorporated in order to be able to use a larger more efficient propeller. This can be a traditional gear box, coaxial planetary gears or a

Types

There are as many types of electric boat as there are boats with any other method of propulsion, but some types are significant for various reasons.

• Historical and restored electric boats, such as the Mary Gordon Electric Boat, exist and are often important projects for those involved.

• Range anxiety is a common concern for those considering electric propulsion on a boat. In 2018, the crew of Rigging Doctor on board Wisdom crossed the Atlantic Ocean with an electric motor.^[19]

• Canal, river and lake boats. Electric boats, with their limited range and performance, have tended to be used mostly on inland waterways, where their complete lack of local pollution is a significant advantage. Electric drives are also available as auxiliary propulsion for sailing yachts on inland waters.
• Electric outboards and trolling motors have been available for some years at prices from about $100 (US) up to several thousand. These require external batteries in the bottom of the boat, but are otherwise practical one-piece items. Most available electric outboards are not as efficient as custom drives, but are optimised for their intended use, e.g. for inland waterway fishermen. They are quiet and they do not pollute the water or the air, so they do not scare away or harm fish, birds and other wildlife. Combined with modern waterproof battery packs, electric outboards are also ideal for yacht tenders and other inshore pleasure boats.
• Electric personal watercraft have been invented but yet to be fully commercialized. These watercraft use a high powered internal battery systems that are waterproofed and propel the vessel at high speeds using a jet drive propulsion. The most first successful project of electric personal watercraft is by United States Company ELAQUA Marine.^[20]
• Cruising yachts usually have an auxiliary engine, and there are two main uses for it: One is to power ahead or motor-sail at sea when the wind is light or from the wrong direction. The other is to provide the last 10 minutes or so of propulsion when the boat is in port and needs to be manoeuvred into a tight berth in a crowded and confined marina or harbour. Electric propulsion is not suitable for prolonged cruising at full power although the power required to motor slowly in light airs and calm seas is small. Regarding the second case, electric drives are ideally suited as they can be finely controlled and can provide substantial power for short periods of time.

Official videos for Ampere
Video on YouTube

• Commercial ferries:

Norway's first battery-electric ferry is

life cycle analysis that 61 of Norway's 112 diesel ferry routes could be replaced by electric ferries with a payback time of 5 years. The analysis includes auxiliary costs such as chargers, grid, and so on.^[25]

In Finland

Aura River to Abo, was converted to all-electric propulsion in April 2017. The vessel was introduced as a wood-burning steam ferry in 1904, converted to diesel operation in 1955 and now provides a continuous daily service from 0615 to late evening for foot and cycle passengers on battery power. Charging takes place at night.^[26]

Other projects are considered in Canada, Sweden and Denmark.[27]^[28][29]

India's First Solar Ferry, a 75-passenger boat, that is powered by sun and grid charging with lithium batteries, began service in 2017.^[30] Based on the predictions of consumption the payback time is 3 years.^[31][32][33]

Some ferries can charge their onboard batteries while docked by using a pantograph.^[34]

On the other hand, ferries can include, sometimes free,

electric motorcycles and electric cars.^[35][36]

• Diesel–electric hybrid: There is a third potential use for a diesel auxiliary and that is to charge the batteries, when they suddenly start to wane far from shore in the middle of the night, or at anchor after some days of living aboard. In this case, where this kind of use is to be expected, perhaps on a larger cruising yacht, then a combined diesel–electric solution may be designed from the start. The diesel engine is installed with the prime purpose of charging the battery banks, and the electric motor with that of propulsion. There is some reduction in efficiency if motoring for long distances as the diesel's power is converted first to electricity and then to motion, but there is a balancing saving every time the wind-, sail- and solar-charged batteries are used for manoeuvring and for short journeys without starting the diesel. There is the flexibility of being able to start the diesel as a pure generator whenever required. The main losses are in weight and installation cost, but on the bigger cruising boats that may sit at anchor running large diesels for hours every day, these are not too big an issue, compared to the savings that can be made at other times. An example is the fishing boat Selfa El-Max 1099,^[37] with 135 kWh battery and 80 kW diesel generator.^[38] An LNG-powered supply vessel started operation in 2016 with a 653 kWh/1600 kW battery acting as spinning reserve during dynamic positioning, saving 15-30% fuel.^[39]
• Solar powered: A boat propelled by direct solar energy is a marine solar vehicle. The available sunlight is almost always converted to electricity by solar cells, temporarily stored in accumulator batteries, and used to drive a propeller through an electric motor. Power levels are usually on the order of a few hundred watts to a few kilowatts. Solar powered boats started to become known around 1985 and in 1995 the first commercial solar passenger boats appeared.^[40] Solar powered boats have been used successfully at sea. The first crossing of the Atlantic Ocean was achieved in the winter of 2006/2007 by the solar catamaran Sun21.^[41][42] (see also List of solar-powered boats)

Wired electric boats

Trolley boats are a special category of electric boats are the vessels receiving their electrical power by wire. This may involve overhead wires, where one or two wires are fixed over the water and the boat can make contact with them to draw electric current, or a waterproof tether cable may be used to connect the boat to shore. In case of a single overhead wire the electrical circuit has to be closed by the water itself, giving rise to a larger resistance and corrosion of the electrodes. In case of two wires no electric current has to be sent through the water, but the twin wires, which cause a short-circuit whenever they come into contact with each other, complicate the construction.

Naturally the boat has to stay close to the wire, or its tether point, and therefore it is limited in its manoeuvrability. For ferries and on narrow canals this is no problem. The Straussee Ferry in Strausberg, Germany is an example. It crosses a lake along a 370 m trajectory and is powered by 170 V from a single overhead wire. The Kastellet ferry crosses a 200 metres (660 ft) wide shipping channel in Sweden, using a submergible tethered supply cable which is lowered to the sea-bed when the ferry is docked at the opposite terminal to its tethering point.

In the

Marne-Rhine Canal a bipolar overhead line provides 600 V DC to an electrical tug, pulling itself and several ships through the 4877 m tunnel along a submerged chain. This prevents the buildup of diesel exhaust fumes in the tunnel. Another example was the experimental electrical tug Teltow [de] on the Kleinmachnower See, 17 km south-west of Berlin. It was used from 1903 until 1910 and had current collection poles based on those used by trolley buses

.

Pollution and embodied energy

Further information: Embodied energy

All the component parts of any boat have to be manufactured and will eventually have to be disposed of. Some pollution and use of other energy sources are inevitable during these stages of the boat's life and electric boats are no exception. The benefits to the global environment that are achieved by the use of electric propulsion are manifested during the working life of the boat, which can be many years. These benefits are also most directly felt in the sensitive and beautiful environments in which such a boat is used.

A 2016 life-cycle study in Norway states that electric ferries and hybrid offshore supply ships compensate for the environmental effects of producing lithium-ion batteries in less than 2 months.^[43]

Historic debate

The British

UK electricity system. Jamie Campbell argued against electric boating on four main counts, which were rebuffed by Kevin Desmond and Ian Rutter of the Electric Boat Association. Jamie Campbell asserted that electric propulsion can no more be justified afloat than a Seagull outboard motor, proposing wooden sailing boats and rowing dinghies

as "by far the most environmentally sensitive and renewable options for recreational boating".

Electricity production

Campbell asserts that the lack of pollution from an electric boat "reeks of nimbyism" as "the discharge is all in someone else's back yard" and that the provision of re-charging points may involve digging up miles of habitat. Desmond responds that while there is no doubt that rechargeable batteries derive their energy from power stations (when not charged on board by solar and wind generation), noisier internal-combustion-engined boats obtain their fuel from even further away and that, once installed a power cable is less environmentally disruptive than a petrol station. Rutter notes that electric boats tend to recharge overnight, using 'base load'.

Efficiency

While there are losses in the charge/discharge cycle and in the conversion of electricity to motive power, Rutter points out that most electric boats need only about 1.5 kW or 2 hp to cruise at 5 mph (8 km/h), a common maximum river speed and that a 30 hp (22 kW) petrol or diesel engine producing only 2 hp (1.5 kW) is considerably more inefficient. While Campbell refers to heavy batteries requiring a "load-bearing hull" and "cranky, even unseaworthy vessels", Desmond points out that electric boaters tend to prefer efficient, low-wash hull forms that are more friendly to river banks.

Pollution

Campbell discusses the pollution that "traditional" batteries put into the water when a boat sinks, but Desmond says that electric boats are no more liable to sinking than other types and lists the leakage of fuel, engine oil and coolant additives as inevitable when an internal-combustion-engined boat sinks. Rutter points to the "very nasty cocktail of pollutants" that come out of a diesel wet exhaust in normal use.

Battery manufacture

Campbell mentions "all manner of noxious chemicals ... involved in battery manufacture", but Rutter describes them as being "lead and sulphuric acid with a few extra trace metals in a modest plastic box" with a potential lifetime of 10–12 years. Desmond says that the US has a 98% recycling rate for lead acid batteries and that the battery and lead-smelting industries observe some of the tightest pollution control standards in the world.

The article mentions 25% and 30% discounts being offered to electric boaters by the UK

Broads Authority and that battery powered vehicles have 3⁄5 the carbon footprint of their petrol equivalents. It is claimed that a typical recharge after a day's cruising costs £1.50, without the use of solar or wind power.^[44]

Solar ships

The first passenger solar vessels started to appear in Switzerland in 1995 with the Solifleur (pictured above), which was also the first solar vessel to feed more energy into the electricity grid than it consumed, on a yearly average, via a grid connection when docked.^[45]

In 2010, the Tûranor PlanetSolar, a 35-metre long, 26-metre wide catamaran yacht powered by 537 square metres of solar panels, was unveiled. On 4 May 2012 it completed a 60,023 kilometres (37,297 mi) circumnavigation of the Earth in Monaco after 585 days and visiting 28 different countries, without using any fossil fuel. It is so far the largest solar-powered boat ever built.^[46]

India's first solar ferry – the Aditya – a 75-passenger boat fully powered by sun, is under construction. It is expected to be completed by the middle of 2016.^[31]

Japan's biggest shipping line

Toyota Motor Corporation.^[47][48][49]

The

Skysails.^[51]

List of battery-electric ships

See also: List of solar-powered boats and Hybrid ferry

List of battery-electric ships, charged mainly from shore power

Year	Name	Country	Battery energy MWh	Charge power MW	Charger type	Notes / Refs
2015	MV Ampere	Norway	1	1.2	Gravity plug Pantograph	Car/passenger ferry[52][53]
2016	MS Vision of the Fjords	Aurlandsfjord, Norway	1.8	0.9	Gravity plug	Carbon fibre hybrid electric catamaran sightseeing vessel (max speed 19.5kn)[54]
2017	Aditya	India	0.05	0.03	Manual	75 passenger solar ferry[55]
2017	MF Tycho Brahe	Denmark/Sweden	4.16	11	Robot plug	HH Ferry route[56][57][58]
2017	MF Aurora [no]	Denmark/Sweden	4.16	11	Robot plug	HH Ferry route[56][57][58]
2017	Elektra	Finland	1		Gravity plug	Similar to Ampere[59][60]
2017		China	2.4			Coal ship[61]
2018	MS Future of the Fjords	Aurlandsfjord, Norway	1.8	0.9	Gravity plug	Carbon fibre catamaran sightseeing vessel (max speed 19.5kn). Sister to Legacy of the Fjords.[54]
2019	E-ferry Ellen	Denmark	4.2	4.4	Automatic plug	Car/passenger ferry[62][63]
2019	Junlyu	China				Yangtze River in Wuhan[64][65]
2019	Herjólfur	Iceland	3	2.5	Robot plug	Sails a 6.5 NM route between Vestmannaeyjar and Landeyjahöfn.
2020	Gee's Bend	USA	0.27			15 Car / 132 passenger ferry[66]
2020	Gisas Power	Turkey	2.9			Tug[67]
2020	MS Legacy of the Fjords	Oslofjord, Norway	1.8	0.9	Gravity plug	Carbon fibre catamaran sightseeing vessel (max speed 19.5kn). Sister to Future of the Fjords.[54]
2021	Bastø Electric	Norway	4.3	7.2		Moss–Horten, 200 cars[68]
2021	Grotte	Denmark	1.1		Plug	Car/passenger ferry[69]
2021	Sparky	New Zealand	2.8		Shore	Harbour tugboat, diesel hybrid[70][71]
2022	Ika Rere	New Zealand		0.3[72]	Type 2 Combo[73]	Passenger Ferry[74]
2022	Yangtze River Three Gorges 1[75]	China	7.5			100 km Yangtze River.[76] 1,300 passengers[77]
2023	Barracuda	Mumbai, India	0.2	0.01	Slow charge	GRP, hybrid solar-electric catamaran work boat (max speed 12.5 kn with 6 kW solar plant)[78]

• Gallery of battery ships
• 
  MV Ampere
• 
  MF Tycho Brahe
• 
  E-ferry Ellen

Solar electric catamaran vessel to carry at least 50 passengers.^[79]

See also

• Catalina 30
• Cruising
• DC distribution system (ship propulsion)
• e5 Project
• Electric aircraft
• Electric battery
• Electric outboard motor
• Electric vehicle
• Frisian Solar Challenge
• Hydrogen-powered ship
• Integrated electric propulsion
  • Diesel–electric transmission
  • Turbine-electric transmission
• Lloyd's Register
• Open source hardware
• Oceanvolt
• Renewable energy
• Solar Splash
• Trolley boat

References

1. ^ Sandith Thandasherry (10 July 2021). Solar Electric Boats: Plan, Build and Benefit. Emerging Technology News.
2. ^ ^{a b} The Oarsman's and Angler's Map of the River Thames from its source to London Bridge (1991. Old House Books, Devon ed.). James Reynolds & Son, London. 1893.
3. ^ Electrical Review. 201 (7). 12 August 1977. {{cite journal}}: Missing or empty |title= (help)
4. ^ ^{a b} Sandith Thandasherry (2023): Technology choices of a medium speed electric ferry. Research gate 20.Aug.2023.
5. wood engravings
   in the Electrical Review, Vol.XI, No.255, 14 October 1882, pp.296 and 297
6. ^ "Batteries". Mary Gordon Trust. Archived from the original on 6 June 2014.
7. ISBN 0-7509-1015-1
    : many references to Moritz Immisch's pioneering work with electric boats on pages 14-29; pages 30-40; pages 149-150, 166-169, and certain other pages
8. ^ "Mary Gordon Electric River Boat". Archived from the original on 7 June 2010. Retrieved 31 May 2010.
9. ^ "The story of solar powered boats". Archived from the original on 8 June 2010. Retrieved 31 May 2010.
10. ^ "History of our Classic Motor Yachts". Elco. Archived from the original on 10 July 2011. Retrieved 21 February 2011.
11. ^ "Bayerische Seenschifffahrt GmbH" [Bavarian Lakes Maritime Ltd.] (in German). Bavarian State Ministry of the Interior. Archived from the original on 29 September 2011. Retrieved 11 July 2011.
12. ^ "Geschichtliche Hintergründe" [Historical Background] (in German). Bayerische Seenschifffahrt. Archived from the original on 10 December 2011. Retrieved 11 July 2011.
13. ^ "Electric Mobility: Electric Boats on Bavaria's Lake Koenigssee – Mobility & Motors – Pictures of the Future – Innovation – Home – Siemens Global Website". 21 October 2014. Archived from the original on 21 October 2014. Retrieved 11 March 2023.
14. ^ "General Dynamics Corporation", Encyclopædia Britannica (15th ed.), 1993
15. ^ Kevin Desmond (2017). Electric Boats and Ships: A History. McFarland Books.
16. ^ Toll, Micah (18 October 2021). "I tested a flying electric boat and it was even cooler than it sounds". Electrek. Archived from the original on 19 October 2021.
17. ^ "The little (electric) engine that could: The Port of San Diego unveils the nation's first all-electric tug boat". San Diego Union-Tribune. 11 March 2024. Retrieved 26 March 2024.
18. ^ Tuominen, P., Supponen, S. (2023): Sähköinen autolautta Helsingistä Tallinnaan onnistuisi konttisähköllä. Tekniikka & Talous 1.8.2023.
19. ^ "Husband, wife to sail Atlantic during yearlong voyage". The Baltimore Sun. 24 August 2017. Retrieved 11 March 2023.
20. ^ "Home". Elaqua Marine. Retrieved 25 February 2024.
21. ^ Stensvold, Tore. "Denne fergen er revolusjonerende. Men passasjerene merker det knapt Archived 4 July 2015 at the Wayback Machine" Teknisk Ukeblad, 20 March 2015.
22. ^ Stensvold, Tore. "Nå lader batterifergen mer enn hun trenger Archived 16 July 2015 at the Wayback Machine" Teknisk Ukeblad, 13 May 2015.
23. YouTube
24. ^ "Batterifergen har måttet stå over avganger. Nå er løsningen klar". Teknisk Ukeblad. 18 November 2016. Archived from the original on 18 November 2016. Retrieved 19 November 2016.
25. ^ Stensvold, Tore. "Lønnsomt å bytte ut 70 prosent av fergene med batteri- eller hybridferger Archived 5 January 2016 at the Wayback Machine" Teknisk Ukeblad, 14. August 2015. In English
26. ISSN 2166-210X
    .
27. ^ Electric ferry jolts discussion over powering ships in B.C. Archived 16 July 2015 at the Wayback Machine Vancouver Sun
28. ^ Sweden launches world's first quick-charging electric passenger ferry Archived 5 September 2015 at the Wayback Machine GizMag
29. ^ "Electric drive train by Visedo to equip world's largest electric ferry". 15 June 2015. Archived from the original on 4 March 2016. Retrieved 18 August 2015.
30. ^ "Kerala Govt. Commissions India's First Solar-Powered Boat, Paves the Way for a Greener Tomorrow". The Better India. 11 May 2016. Retrieved 24 May 2016.
31. ^ ^{a b} "India's First 75-Seater Solar Ferry Readies To Test The Waters". OfficeChai. 16 January 2016. Archived from the original on 30 January 2016. Retrieved 4 February 2016.
32. ISSN 0971-751X
    . Retrieved 24 May 2016.
33. ^ "Kerala Govt. Commissions India's First Solar-Powered Boat, Paves the Way for a Greener Tomorrow". The Better India. 11 May 2016. Archived from the original on 26 May 2016. Retrieved 24 May 2016.
34. ^ "FerryCHARGER". Archived from the original on 10 March 2019. Retrieved 21 November 2018.
35. ^ "Electric car charging on Irish Ferries routes". Archived from the original on 20 November 2015. Retrieved 24 August 2018.
36. ^ "Can I Charge My Electric Car Onboard?". Archived from the original on 24 August 2018. Retrieved 24 August 2018.
37. ^ Valle, Marius. Or the Nova Luxe re-fit on an Aquila 44. https://www.novaluxeyachts.com/electric-projects?lightbox=dataItem-jww6lc4j "Dette er Norges første fiskebåt med elmotor Archived 16 August 2015 at the Wayback Machine" Teknisk Ukeblad, 31 July 2015.
38. ^ "Batterifiskebåten Karoline: Ett år uten driftsavbrudd". Teknisk Ukeblad. 22 August 2016. Archived from the original on 23 August 2016. Retrieved 22 August 2016.
39. ^ "Første i verden: Her skal batterier erstatte motor i kritiske situasjoner". Teknisk Ukeblad. 11 October 2016. Archived from the original on 11 October 2016. Retrieved 11 October 2016. batteripakken ombord på Viking Energy erstatter en hovedmotor som reserve (spinning reserve)
40. ^ "Solarschiffe für die Expo?". Umwelteinsatz.ch. Archived from the original on 9 October 2007. Retrieved 20 June 2009.
41. ^ "The world's first crossing of the Atlantic on a solar boat". transatlantic21. Archived from the original on 24 May 2009. Retrieved 20 June 2009.
42. ^ "EERE News: EERE Network News – 06 December 2006". Apps1.eere.energy.gov. 6 December 2006. Retrieved 20 June 2009.
43. ^ "Batterier til elferger: Miljøbelastningen er spart inn etter 1,4 måneder". Teknisk Ukeblad. 10 January 2017. Archived from the original on 11 January 2017. Retrieved 10 January 2017.
44. ^
    ISSN 0950-3315. Archived
    from the original on 6 March 2010. Retrieved 13 April 2010.
45. ^ "Solar Ships for the new Millennium". TO Engineering. 15 March 2001. Retrieved 24 December 2022.
46. PlanetSolar. "MS Tûranor PlanetSolar yacht completes her first tour around the world with a success". Charterworld.com. 4 May 2012. Archived
    from the original on 7 May 2012. Retrieved 9 May 2012.
47. ^ "Alternative Energy and Fuel News: ENN – Know Your Environment". ENN. 26 August 2008. Archived from the original on 1 February 2009. Retrieved 20 June 2009.
48. ^ "Japan launches first solar cargo ship". Solardaily.com. Archived from the original on 9 February 2009. Retrieved 20 June 2009.
49. ^ "Solar ship sails the ocean green – National". The Sydney Morning Herald. 15 March 2005. Archived from the original on 4 June 2009. Retrieved 20 June 2009.
50. ^ "The world's first gigayacht". Motor Boat Monthly. 11 June 2010. Archived from the original on 14 June 2010. Retrieved 11 June 2010.
51. ^ "Why". Wally Yachts. Archived from the original on 2 April 2010. Retrieved 11 June 2010.
52. ^ Madslien, Jorn (4 April 2017). "Pining for cleaner air in the Norwegian fjords". BBC News. Archived from the original on 13 August 2018. Retrieved 6 December 2017.
53. ^ Pratt, Joe (15 December 2016), Battery Electric and Hybrid Vessels in Norway and Denmark: Ampere, Vision, and HH Ferries (PDF), Sandia National Laboratories, archived from the original (PDF) on 9 August 2017, retrieved 5 December 2017
54. ^ ^{a b c} "Our boats". The Fjords AS. Retrieved 4 June 2023.
55. ^ "Significant Small Ships 2017". RINA.
56. ^ ^{a b} Kane, Mark. "World's Largest Electric Ferries: 4.16 MWh Battery, 10 MW Charging". insideevs.com. Archived from the original on 17 December 2017. Retrieved 16 December 2017.
57. ^ ^{a b} Slinn, Tony (22 March 2017). "The World's Largest Emission-Free Electric Ferries". NauticExpo e-Magazine. Archived from the original on 10 August 2018. Retrieved 16 December 2017.
58. ^ ^{a b} Tornbjerg, Jesper (25 August 2017). "Færgen er i stik om få minutter". Dansk Energi (in Danish). Retrieved 16 December 2017.
59. ^ Knight, Stevie, 'Elektra': Commercial battery ferries become a reality, archived from the original on 6 December 2017, retrieved 5 December 2017
60. ^ "VIDEO: Plugging in Finland's first electric ferry". marinelog.com. Marine Log. 20 November 2017. Archived from the original on 6 December 2017. Retrieved 5 December 2017.
61. ^ 于小明. "Fully electric cargo ship launched in Guangzhou – Business". chinadaily.com.cn. China Daily. Archived from the original on 10 December 2017. Retrieved 6 December 2017.
62. ^ "FAQ; battery". Archived from the original on 19 April 2019. Retrieved 30 August 2019.
63. ^ Murray, Adrienne (14 January 2020). "Plug-in and sail: Meet the electric ferry pioneers". BBC News. Retrieved 14 January 2020.
64. ^ Butler, Jeff (10 December 2019). "China's electric ferry is first in the country". Plugboats.
65. ^ "All-electric passenger ship a first – Chinadaily.com.cn". global.chinadaily.com.cn. 6 December 2019.
66. ^ "First all-electric ferry in U.S. reaches milestone". WorkBoat. 6 August 2020.
67. ^ "World's 1st all electric tugboat now at work in Istanbul". Plugboats. 9 September 2020.
68. ^ "World's Largest Electric Ferry Now Operational in Norway". InsideEVs. 2 March 2021.
69. ^ Hede, Mark Michael (1 October 2021). "Ny eldrevet Fanø-færge til 80 millioner lagde sikkert fra land". JydskeVestkysten. Archived from the original on 1 October 2021.
70. ^ "Video: Ports of Auckland welcomes world's first e-tug". EVs & Beyond. 8 June 2022.
71. ^ "Reversed Stern Drive Tug 2513 Electric" (PDF). Archived (PDF) from the original on 9 October 2022.
72. ^ "New Zealand electric ferry operator brings forward order for second vessel". 7 April 2023.
73. ^ "East By West 19m Ferry". 7 April 2023.
74. ^ "Southern hemisphere's first electric ferry launched in Wellington". 7 April 2023.
75. ^ "Largest electric cruise ship makes debut – People's Daily Online".
76. ^ Doll, Scooter (31 March 2022). "'World's largest electric cruise ship' makes maiden voyage in China with a whopping 7,500 kWh in battery power". Electrek. Archived from the original on 2 April 2022.
77. ^ "Largest electric cruise ship makes debut – People's Daily Online".
78. ^ "'India's fastest' solar-electric boat Barracuda launched". The Hindu. 14 December 2023. Retrieved 19 December 2023.
79. ^ "ECOMARINE BD". ECOMARINE BD. Retrieved 11 March 2023.

External links

• Electric Boat Design
• Electric passenger Boat Designed for the city of Bordeaux (France)
• Electric Boat Association (UK nonprofit)
• Electric Boat Association (Australia nonprofit)
• Electric Boat Association (US nonprofit)
• Electric Seas Organization (US nonprofit)
• Getting to Zero Coalition
• Project of making of 10 Passenger Solar Boat Archived 9 July 2017 at the Wayback Machine